A preliminary survey revealed that the average Vietnamese household spends nearly 30 percent of its monthly income on electricity, an official said.

Dam Xuan Hiep, general secretary of the Vietnam Electrical Power Association, told Tuoi Tre newspaper that, in other countries, all energy costs, including power and fuel, rarely exceed 20 percent of the total household income.

Hiep said Vietnamese are spending more on electricity despite the fact that power prices in the country are low.

The average household electricity bill is about 5 US cents per kilowatt-hour. An official has said it's much cheaper than a glass of iced tea, which costs around 10 cents.

Vietnam will raise electricity prices by 15.3 percent next month in a bid to help attract investment in new power plants.

Hiep said it would take some time after the price hike for investment to come into the sector.